package day12.util;

import java.util.Random;

/**
 * @author chenshijie
 * @date 2024/1/1 17:02
 */

public class IDUtil {
    public static int randomNumber() {
        return new Random().nextInt(900000000) + 100000000;
    }

    public static boolean isNumeric(String str){
        if (str == null) {
            return false;
        }
        for (int i = str.length();--i>=0;){
            if (!Character.isDigit(str.charAt(i))){
                return false;
            }
        }
        return true;
    }
}
